HIF1A and cancer: The levels of positive HIF-1α expression according to pTNM categories and histological grade was as follows: 26.7 % (4/15) in pT1-T2 and 94.1 % (16/17) in pT3-T4 tumors, 54.5 % (12/22) in pN0 and 80 % (8/10) in pN1-3 and 10 % (1/10) for well-differentiated tumors, 75 % (9/12) for moderately-differentiated cancers, and 100 % (10/10) for poorly-differentiated tumors.